And what's the problem with Geometry?
We have been given a diagram and we need to find the value of arc angle a.
According to one of the circle theorems the angle at the centre of a circle is twice the angle at the circumference subtended by the same arc.
Therefore, arc angle a will be twice of the angle at circumference, that is, 34 degrees.
Therefore, value of angle a is:

Answer:
The answer is GRAPH
Step-by-step explanation:
Step-by-step explanation:
40° + 90° + 90° + angle ACB = 360°
220° + angle ACB = 360°
angle ACB = 360° - 220°
Therefore angle ACB = 140°
Hope it will help :)